/Engine/Source/Editor/MaterialEditor/Public/IMaterialEditor.h
Creates a new material expression composite, along with related child pinbase expressions
UMaterialExpressionComposite* Newly created material expression composite
virtual [UMaterialExpressionComposite](API\Runtime\Engine\Materials\UMaterialExpressionComposite) * CreateNewMaterialExpressionComposite ( const FVector2D & NodePos, const class [UEdGraph](API\Runtime\Engine\EdGraph\UEdGraph) * Graph )